Pro divers are less headache-prone: study

NEW YORK (Reuters Health) - Despite concerns that water pressure and other stresses might promote headaches, professional scuba divers may actually get fewer of the painful attacks, overall, than other healthy people, say Italian researchers.

Published in the journal Headache, their study compared the number of "cephalalgia attacks" -- headaches of all kinds -- experienced by 201 male professional divers and a control group of healthy men who didn't dive. The divers were about 30 percent less prone than controls to get headaches in general, and when they did, the divers got fewer headaches per month.

Though the study's findings are limited by a small sample size, its lead author Dr. Roberto Di Fabio, a neurologist, thinks the results will help determine how diving affects professional divers.

Di Fabio speculated that the divers' overall health could be one reason they experience fewer headaches. Or, he said, the diving itself may offer some protection.

"Exercise would be useful to make our brain less sensible to stress and avoid that even slight stimuli could trigger migraine crises," Di Fabio told Reuters Health in an email. "Therefore, diving as well as other aerobic sports could help in reducing the number of attacks of migraine."

Doctors have wondered whether the physical and mental stresses of diving might promote headaches or exacerbate the tendency of people who have migraines, for instance, to get more attacks.

Last Updated: 2011-10-21 15:25:14 -0400 (Reuters Health)

High underwater pressure puts a person in danger while diving. Failing to ascend or descend properly can cause injury to vital organs as the gases within them compress or decompress. Improper diving techniques can also cause gas bubbles to form in the bloodstream -- a condition known as the bends.

Divers are also known to display certain structural changes in their brain matter, and may regularly get tiny clots in the brain's blood vessels as a result of the physical stresses of diving.

To find out whether such effects lead to headaches, Di Fabio's team recruited 201 divers working for the Italian Fire and Rescue Department and a set of healthy men, matched to the divers in age, who had never dived. Both groups underwent neurological exams, then for one year they logged the details of their tension headaches and episodes of migraine with or without aura.

During the study period, 22 percent of the control group experienced headaches compared to 16 percent of the professional divers. Moreover, the divers who did get headaches had fewer of them per month than the controls.

The number of subjects who got migraines in both groups was low -- 4.5 percent of the divers and eight percent of the controls. Tension headaches were a little more common -- ten percent of divers got them, compared to 13.5 percent of the controls.

Di Fabio told Reuters Health that the findings cannot be generalized to a wider population, such as recreational divers.

"Recreational divers are more difficult to study, because the number of dives are less easily recordable," Di Fabio said.

Also, recreational divers may add other variables to a study.

"The emotional stress that you associate with diving is something you would see more with a recreational diver than a professional population," said Dr. Herbert Newton, professor of neurology and neurosurgery at the Ohio State University Medical Center and a dive medical consultant.

"Professional divers are trained pretty well about the kind of things that you need to look for," said Newton. "Recreational divers know a little about that but it's not nearly as extensive."

Regardless of experience level, Newton said divers should get out of the water if they get a headache.

"If you go under water and you start developing a symptom of a migraine or headache, it would be safer to abort the dive and take care of the headache on the boat or on land," said Newton.